Crown Molding Coping Cuts

When you are shaping moldings, such as a clamshell or colonial baseboard, or crown molding that is going to meet at inside corners, or a chair rail, the best technique for joining them s with a coped joint. This type of joint is made with a coping saw to make crown molding coping cuts.

The saw will cut a profile onto one piece of molding so that it will fit over the contours of the other piece. It is possible to use a miter joint for this application, but it can be more difficult to get right, especially on drywall. Crown molding coping cuts made with a coped joint will not come apart as easily as a mitered joint when the woods contacts and expands with the weather.

Coping Saw and Blades

For precise cutting of intricate or irregular shapes with precise control.

For crown molding coping cuts, the first item you will need is the saw- this can be the power miter saw or the coping saw. You will also need a miter box and a backsaw. It is also necessary to have a coping saw blade for fine woodcutting. It will also be necessary to have a rattail file and a clamp sufficient for your project scope.
Beginning the Installation

Cut and measure the first piece of molding at 90 degrees. These crown molding coping cuts are so that it will fit into the inside corner. You may need to cut the other end to fit between walls, or maybe cut a miter at a corner, or to cut an open miter to make it possible to join another piece onto it.

When both cuts have been made, you will need to test it to make sure of the fit, and to make any corrections that are necessary. When you are sure of the fit, install that piece of the molding.

To continue your crown molding coping cuts, place the molding that you want to cope on your saw table or in your miter box, face up. Cut an open miter, 45 degrees, at the end that will join the molding that has been installed. This open miter is where the molding face is shorter than the molding back. This cut will create a profile where the end grain that is exposed will meet the face.

Then, the molding should be clamped in a wood vise, or onto a sawhorse of workbench. Start making your crown molding coping cuts on the molding’s thin edge. Put the blade onto the line use your thumb to guide the start of the cut.

Begin slowly in order to avoid splintering the edge. Clamshell molding has a continuous curved profile, and for this type you can make the entire cut at once. For more complicated moldings, you should stop cutting one direction and start a different cut, sometimes continuing this several times.

Testing and Fine Tuning

When your crown molding coping cuts have been made, test the fit. You can hold it in place, or against a piece of scrap molding. The other end should not be cut until the coped joint has been tested and any adjustments have been made. This will ensure that it will not be too short, in case the coped end needs to be recut.

The final step for your crown molding coping cuts is to use a rattail file for your fine tuning. This will remove any high points that are preventing the coped end from a tight fit. When the fit is good and tight, cut the other end and install the molding.